This invention relates to an optical scanning system for use in a photocopying environment.
Prior art relevant to this invention is typified by the optical system in the Xerox 4000 copier. In that system, represented schematically in FIG. 1, a stationery object is scanned by a lens which projects a composite image of the same onto a moving photoreceptor drum. In the case of 1:1 image magnification, the lens is located midway between object and image plane and moves at half the tangential velocity of the photoreceptor drum. Due to the nature of the system, an ordered image is composed on the moving photoreceptor during only one direction of scan. The return travel of the optics represents lost time in the system. As a result, quick return or flyback arrangements for these scanning optics are used to minimize such lost time.
It is an object of this invention to provide a scanning optical system of the type just described in which scanning is performed and an ordered image projected during both directions of lens travel.